1. Technical Field
The present invention relates to expandable shoes that may be adjusted longitudinally.
2. Discussion of Related Art
Some attempts have been made to provide expandable shoes, which can purportedly withstand day-to-day use. U.S. Pat. No. 3,389,481, for example, discloses a shoe in which a two plate assembly is disposed between an inner and a disjointed outer sole, having overlapping front and back portions. One of the plates includes a spring tongue, and the other plate includes two apertures to receive the spring tongue, each aperture corresponding to a shoe size. To adjust the shoe size, a screw which extends through the heel and into the disjointed soles is removed. The shoe may then be pulled apart allowing the disjointed sole to separate until the spring tongue engages the next aperture. Thus the shoe size may be lengthened by one size, but apparently the size cannot be controlled finely or reduced. The shoe includes two crinkled leather portions 34, one on each side of the shoe, to facilitate expansion of the shoe.
WO 01/33986 describes an expandable shoe. The expandable shoe includes an outer shell having a front and a rear outer assembly each attached to a flexible, expandable segment. An adjustable inner assembly is disposed within the outer shell and includes a control mechanism, accessible from the outer shell, that may be urged from a lock state into a state in which the inner assembly and outer shell may be adjusted. A visualization window provides a view port to the inner assembly.
Though WO 01/33986 details a desirable expandable shoe design, certain improvements thereto have been discovered to improve ergonomics, torsional rigidity, handling, and the construction of the shoe.